Hmmm. Basically all the time
I understand the urge to reflect music theory, but this is intended for computers and they prefer 0-indexed. Ok, I could just add one to “my” 0-indexed value and use the op, but things like %7 doesn’t play well with this. Also N 0 returns 0, which makes total sense, I’d expect N.S 0 0 0 to return 0 as well.
If all my input for an op like this were coming from patterns (iow: values I put in there) the problem might not that big, but most of my values are calculated or at least transformed by code, so it’s awkward that N.S is different from everything else.
So no concrete example, hope you see what I mean. If I think hard + long I might come up with a concrete example later, but maybe that’s not necessary 
Exactly! Besides that N.S is broken (or I’m using it wrong) on negative degrees.
I went ahead an implemented my N.Q (had to pick a non-clashing name for now). This is basically how I hoped N.S would work, wrapping across octaves (including negative degrees) and 0-indexed. Hope you find to the time to try it out and enjoy it, it feels really good here on my teletype
Not heavily tested, but seems to work as expected…
Oh, and yes, it reuses all tables…
NB: patch-level 0, but you’ll probably figure that out anyhow 
NB: there’s a precious attempt commented out, I’ll clean that up in a minute… (EDIT: done!)
https://raw.githubusercontent.com/attejensen/eurorack_firmware_patches/master/teletype_op_nq.diff
EDIT: Ok, the jury’s still out on 0/1-indexed. After working a bit with the 0-indexed version, I made a 1-indexed version, I’ll report back when I hear from the jury 